I was experimenting with the Riftwalker bonus quests and found that completing the ascendant bonus quest prior to the greater bonus quest locks out the greater walker's bonus quest reward.
I tried 10 times to verify it wasn't me screwing it up. No, a fresh charm in the intended order went correctly.
If this is intended it sure isn't clear. I also am likely the only idiot forgetting long enough to go out of order.